Grinding machine



Aug. 22, 1939. HUERNST ET AL GRINDING MACHINE 6 Sheets-Sheet 1 Filed Oct20, 1936 ATTORNTY.

Aug. 22, 1939. H. ERNST ET AL GBINDING MACHINE Filed Oct. 20, 1936 6Sheets-$heet 2 ATTORNEY.

6 sneets sneez 3 Zia]? H. ERNST ET AL GRINDING MACHINE Filed Oct. 20,1935 INVENTOR. fim" ffl/Xfi" aim/1M1 ATTORNEY.

Ila-5 Aug. 22,- 1939. H E NST ETAL 2,170,494

GRINDING MACHINE Filq on; 20, 19:56 6 Sheets-Sheet 4 ATTORNEY.

Aug. 22, 1939. H. ERNST El AL 2,170,494

GRINDING MACHINE Filed Oct. 20, 1936 6 Sheets-Sheet 6 I flaw/$5241 Wmllllll. u ii] INVENTOR. fikm" fin.

A'I'I'ORNEY.

h k\- l-.-t i v @QQ w NM 0 RM 5 ANN kw QM mm v EN www a. a MN QM a? g mmv. uu Q Q \m m Q 3 R Q m Q Q Q. QWN a v v S N a v .Q, &w J \Qw mama Q0\\N N .QN .QN Q v 5 m. a W M\ RR v \NN QNN QN N 7 Q Nk k n EN QN Q Q R v5 RN 3 .& ww N w\ R g i Z Q 2N wm m .RN MM Na 7 \N Q1 Patented Aug. 22,1939 UNITED STATES aim-194 GRINDING MACHINE- Hans Ernst, Cincinnati, andAlbert H. Dali, Silverton, Ohio, assignors to Cincinnati GrindersIncorporated, Cincinnati, Ohio, a corporation-o! Ohio Applicationv(lctobcr 20, 1936, Serial No. 106.596

22 Claims.

This invention relates to machine tools and more particularly toimprovements in the transmission and control mechanism thereof.

One of the objects of this invention is to provide an improvedtransmission and control mechanism which is especially adaptable forcontrolling the relative movements of a grinding wheel in a machinehaving capacity for relatively large work and in which the movements ofthe wheel must necessarily be relatively large.

Another object of this invention is to provide a transmissiion andcontrol mechanism for the purposes described which is comparativelysimple in construction, but which is capable of yielding all thedesirable control eiiects necessary to the successful operation of amachine of the above character.

A further object oi this invention is to provide a transmission andcontrol mechanism which is.

capable of yielding a plurality of ranges of feed rates, all incontinuous succession, together with infinite variation throughout allranges.

Other objects and advantages of the present invention should be readilyapparent by reference to the following specification, considered inconjunction with the accompanying drawings forming a part thereof and itis to be understood that any modifications may be made in the exactstructural details there shown and described, within the scope of theappended claims, without departing from or exceeding the spirit of theinvention.

Referring to the drawings in which like reference numerals indicate likeor similar parts: Figure 1 is a plan view of a machine embodying theprinciples of this invention. I

Figure 2 is an end elevation of the machine in the direction indicatedby the arrows 2-2 .in Figure 1. s

'40 Figure 3 is an enlarged cross sectional view through the wheel slideshowing the means for adjusting the wheel toward and from the worksupport.

Figure 4 is a cross sectional view through the 45 wheel head carriedcarriage taken along the line 4-4 of Figure 1 and showing the finaldriving means for traversing the carriage,

Figure 5 is a detailed section on-the line 5-5 of Figured showing themeans for selecting be- 50. tween manual and powertraverse oi the wheelhead and for selecting between the high and low source of feed rates.

Figure 6 is a detailed section on the line 66 of Figure 3 showing themeans for clamping the cross slide to the traversing slide.

Figure 7 is a fragmentary view with parts broken away looking in thedirection of the arrows 1--1 of Figure 6.

Figure 8 is a section on the line 8-8 oi Figure 2.

Figure 9 is a detailed section taken on the line 5 9-9 of Figure l.

Figure 10 is a detailed sectional view taken on the line i0l0 of Figure9.

Figure 11 is a detailed view taken on the line H-ll of Figure 9. I 10Figure 12 is a sectional view taken on the line l2l2 of Figure 11.

Figure 13 is a diagrammatic view of the transmission and controlmechanism of the machine.

Figure 14 is a plan view of the guide plate as 10 viewed on line H-H ofFigure 5.

Figure 15 is a detail view of the variable delivery pump control.

Figure 161s a. plan view of the control shown in Figure 15. 20

This invention has been illustrated in connection with a roll grindingmachine of the type .shown in Figures 1 and 2 which consists oi. an

elongated fixed bed I0 on which is mounted a headstock ii and atailstock l2, the latter of 25 which is adjustable toward and from theheadstock for set-up purposes. There is also provided a pair ofguideways i3 and I4 upon which is slideably mounted a traversingcaniage. I! which, in turn, supports a transversely movable 30 wheelhead carriage l6,

This invention is concerned with an improved transmission and controlmechanism for controlling'the transverse movements of the wheel head andthe feeding and traversing movements of as the carriage 85.

As shown in Figures 3 and 13, the cross slide I6 is actuated by a pistonI! connected by a piston rod I8 to the slide l6 and .slideabl y mountedin a cylinder is. The opposite ends of this cylinder. are connected bychannels 20 and 2| to ports 22v and 23 of a manually operable reversingvalveil. This valve has a pressure port 25 connected to the delivery ofa constant displacement pump 26 which has an intake 21 through whichfluid is withdrawn from a reservoir, indicated generally by thereference numeral 28. The reversing valve 24 has an additional pair ofports 29 and 30 connected to a returnline 3|.

The plunger 32 of the reversing valve is connected by a crank 33 to anoperating handle 3. When the plunger 32 is shifted to the right, asviewed in Figure 13, the pressure port 25 is connected to port 23whereby fluid is delivered to.

one end of cylinder I! to cause the wheel head i l6 to move toward thework support and when the plunger 32 is shifted to the left of theposimoved by power.

grinding wheel for set-up purposes, and since, as

a matter of fact, each roll that is ground is usually of a diflerentsize it becomes necessary to adjust the grinding wheel for practicallyevery piece of work.

To insure, however, that thegrlnding wheel maintains a definite positionwith respect to the slide l5 and that there is no creepage due to theslight variations in pressure in the opposite end of cylinder I9, aclamping mechanism has been provided for securing the slide l6 to theslide 15.

The details of this clamping mechanism, which are more particularlyshown in Figures 6, "I and 8, comprise a pair of pull rods 35 and 36located on opposite sides of the V guide-way 31 and the are threaded toreceive lock nuts 40. The lower upper ends of these rods pass throughL-shaped clamping members 38 and 39 respectively and ends of these rodsare connected to an equalizer bar 4| .which is adapted to be engaged inthe middle by a pivoted clamping lever 42.

This lever, as shown in Figure '1, is pivotally mounted at one end on afixed stud 43 and at the other end rotatably supports a cam 44 which isactuated by the ball-ended crank 45. The cam 44, which is circular, iseccentrically supported on the shaft 46 and when the parts are in theclamping position shown in Figure 'l, the largest radius of the camengages the undersurface of the block 41, thereby holding the lever 42downward which thereby applies pressure on the equalizer bar 4| and rodsand 36 to cause the'clamping members 38 and 39 to hold the slide in afixed position. The cam is moved into this position by the applicationof fluid pressure on the end of the piston 48 and the clamps arereleased by applying fluid pressure on the end of the piston .49. Asshown, these pistons bear on' the ball-shaped crank 45, piston 48tending to rotate the parts in a counter-clockwise direction and thepiston 49 tending to rotate the parts in a clockwise direc-' tion. Thepistons 48 and 49 are contained in cylinders 50 and 5| respectively andthese cylinders are connected by channels 52 and 53 respectively toports 54 and 55 of a reversing valve 56 having a central pressure port'51 and return ports 59 and 59 on opposite sides thereof. The plunger 60of this reversing valve is urged by-a spring 6! in such a direction thatthe pressure port 51 is connected to the port 54 leading to cylinder 59whereby the cross slide I6 is clamped to the traversing slide 15.Pressure is supplied to the port 51 from a branch line 62 which issupplied with fluid from the constant displacement pump 26. 3

It is, of course, obvious that the clamping mechanism should be releasedbefore the slide is moved and to this end means have been providedwhereby the lever 34 will actuate the reversing valve of the clampingcontrol mechanism, before it finally shifts the plunger 32 into aposition to effect pressure connections to the cross slide actuatingcylinder l9. This mechanism comprises a lever 63 having one end pivotedat 64 and the other end engaging the plunger 60. An intermediateV-shaped portion 65 of the lever is adapted to engage a notch 66 .in theperiphery of a plate 61 fixed for movement with the lever 34. The notchpermits the spring 6| to shift the plunger 60 into the position shown inFigure 13, whereby pressure is connected to cylinder 50. Upon movementof the lever 34 in either direction from the central position in .whichit is shown, the lever 63 will be moved ,in a clockwise direction aboutits pivot 64 and shift the plunger 60 to the right and therebycausefluid pressure to be connected to cylinder 5| with a resultantrelease of the clamping. mechanism. As the lever 34 moves'to shift theplunger 69 it is also moving the reversing valve plunger 32, but thisplunger has sufficient overlap with respect to its ports thatappreciable movement may be efiected before pressure is connected intolines 20 and 2|. Since a certain time element is involved in effectingunclamping and to prevent dissipation of the pressure, which wouldhappen if the operator moved the lever 34 quickly to either of itsextreme positions, an interlock has been provided which limits themovement of the valve plunger 32 so that it will not attain an operativeposition until the clamping mechanism has been released.

This mechanism includes a notched plate 68 integrally connected formovement by the handle 34, and a spring-pressed'pawl 69 adapted to beheld in engagement with said notch, the notch being of suflicient widthto allow a certain amount of lost motion between the pawl and the platewhereby the lever 34 may be moved a sumcient amount to cause shifting ofthe reversing valve 60 to a clamp unlocking position while stillpreventing movement of the plunger 32 to a slide actuating position. Thepawl 69 is pivoted at an intermediate point 10, and a fluid actuaatedplunger 1| engages the other end of the pawl for withdrawing the samefrom engagement with the plate 68. The plunger 1| is slideably mountedin a cylinder 12 which is connected by a channel 13 to a port 14 locatedin the cylinder 5!. When the plunger 49 has'moved a sufficient distanceto release the clamp, the channel 53 which supplies fluid pressure tocylinder 5|, is interconnected with port 14 whereby the fluid pressurewill be connected to cylinder 12 to cause withdrawal of the pawl andpermit further movement of the lever 34. Upon return movement of thelever 34 to its central position, the plunger 48 will be actuated tomove the crank 45 into a clamping position, a cannelure 15 formed in theplunger 49 will interconnect port 14 with exhaust port 16, wherebyaspring 69' may return lever 69 into an interlocking position and effectretraction of piston -1l.

Thus, the first part of the movement of the lever 34 from its centralposition shifts the reversing valve 60 into a position to causeunclamping of the slide by connecting pressure to line 53; andcompletion of the unclamping operation automatically releases the lever34 for by clamping of the slide and resetting of the locking pawl.

In roll grindersit is desirable to have a transmission which isinfinitely variable over a comparatively wide range, and with thisrequirement in view, a transinission and control mechanism 7 has beenprovided which will yield a minimum rate of approximately 1" travel ofthe slide per minute and a fast rate'of approximately 120" per minute,together with the feature of variation between these limits.

It is also desirable that this transmission be of a type which readilylends itself to manual operation.

A careful selection of the elements making up this transmission has beenmade, in view of the fact that a piston and cylinder type of motor doesnot readily lend itself to manual operation of the slide, and because anelectric motor of the variable speed type is limited to a range of 1 to3 so far as infinite variation of speed is concerned. The units of thetransmission, therefore, consist of a variable delivery pump and avariable speed fluid motor, which makes it possible to obtain aninfinite range from 1 to 20, which makes possible.

infinite variations of travel from 1" to 20" per minute of the slide.Additional variation is obtained by combining a constant delivery pumphaving an output equal to the maximum output of the variable deliverypump whereby the range may be increased to obtain infinite variation ofrate from 20 to. 40" of travel a minute. In either of the above cases,the variable speed hydraulic motor is connected by reduction gearing tothe final output, and 'by reducing this reductionby the factor 4, thefirst range is increased to yield infinite variation of rate over athird range from 40" to 80", and the second range increased to yield aninfinite variation of rate .over a fourth range from 80" to 120" perminute and all in continuous succession.

The transmission and control mechanism for traversing the wheel headrelative to the work support will now be described. The fixed bed 18 onwhich the guide ways I3 and I4 are mounted for supporting the carriageI5 is provided with a rack 18 which is engaged by a pinion 88, as shownin Figure 4, secured to the end of a vertical shaft 8|. The shaft 8| isjournaled in the carriage I5 on anti-friction bearings and is rotated bya worm wheel 82 which is, in turn, driven by a worm 83 Referring toFigure 5, the worm 83 is supported on a shaft 84 which has mounted forfree rotation thereon a pair of spur gears85 and 86, gear 85 beinglarger in diameter than gear 86. These gears are in constant mesh withgears 81 and 88 respectively keyed to shaft 88. This shaft is directlyconnected for rotation by an hydraulic motor 88. The gear train 81--85effects in this case a rate reduction of four times that effected bytrain 8886, but it is to be understood that other reductions could beutilized.

The clutch 8| is. splined on shaft 84 intermediate gears 85 and 86 andhas clutch teeth formed on opposite faces for engagement with simiarlyformed clutch teeth on the opposing faces of the gears. Since the gear85 is continuously driven at a slower rate than the gear" 86, and sincethe motor 88 can be driven at a plurality of rates it will be apparentthat the clutch member 88 serves to select between a high series and alow series of feed rates,

The clutch 8| is shifted by a shifter fork 82 fixed on the shifter rod83. The shaft 84 has a gear 84 fixed to the end thereof and adapted tobe interengaged by a shiftable gear 85 for manual rotation of the worm83. The gear 85 is splined on a shaft 86 to the end of which is secureda large sprocket wheel 81 and connected by a chain 88 to a sprocketpinion 88. This pinion is keyed to effect translation of the carriageI5.

The gear 85 is shifted by a fork I83 which is secured to a shifter rodI84. In order to prevent conflict between manual and power operation ofthe worm 83, the shifter rods 83 and I84 are arranged side by side and acommon control lever I85 is provided, and provision made whereby thislever can only shift the clutch 8| or the gear 85 into an operativeposition at a time. In other words, the lever I85 is pivotally mountedat an intermediate point by means of a ballshaped portion I86 and aguide plate I81 is provided in which is formed a. slot I88 having ashape such as that shown in Figure 14. The lever I85 is moved laterallythrough the portion I88 of the slot to select which shifter rod is to bemoved and is movable through the portion I I8 to shift the clutch 8|into either one of its two positions and through the portion I I I toshift the gear 85 into engagementwith gear 84.

Operating fluid is supplied to the motor 98 by a variable displacementpump 2 having intake and delivery ports H3 and H4 respectively which areoperatively connectible by channels H5 and H6 to ports H1 and H8 of astop valve H8. The plunger I28 of this valve is shown ina stop positionin Figure 13, but when the same is shifted to the right of that positionthecannelure I2I interconnects port 8 with port I22, and thereby throughchannel I23 to port I24 of a re-' versing vave 25. In addition thecannelure I26 interconnects port I I1 with port I21, thereby throughchannel I28 to ports I28 and I38 of reversing valve I25. The reversingvalve also has a pair of ports |3I and I32 to which are connectedchannels I33 and I34 respectively through which fluid is supplied to themotor 88. when the reversing valve plunger I35 is in its right handposition, as shown, the pressure is delivered into channel I33 from thedelivery port II 4 of the pump H2 and the fluid returning throughchannel I34 is returned by way of port I38, channel I28, ports I21 and I"of the stop valve and channel I I5 to the intake port 3 of the variabledelivery pump. It wilbe seen that this is in effect a closed circuitwith the intake and delivery ports of the pump connected directly to thetwo ports of the motor.

The reversing valve plunger I35 is power shifted by fluid operable pilotcircuit comprising a pilot valve I36 having a pressure port I31connected by channel I38 to the delivery channel 6 of the variabledelivery pump II 2. Also, the pilot valve has a pair of return ports I38and I48 which are connected .to channel I leading to the intake line II5of the variable delivery pump. In

addition, the pilot valve has a second pair of ports I42 and I43 whichare connected by chan-- nels I44 and I45 respectively to opposite endsof the reversing valve I25. When the plunger I46 of the pilot valve isin its right hand position, as shown in Figure 13, pressure from portI31 will flow to the left end of valve I25 shifting.

plunger I35 into its right hand position and when the pilot valvepiunger I46 is shifted to the left, pressure from port I31 will then bedelivered to the righthand end of valve I25, shifting plunger I 85 toits left hand position.

The pilot valve plunger I46 is connected by a bell crank I41, shown inFigure 12, to a vertical movable slide I48 in which is formed a slot forreceiving one arm I49 of the bell crank. The slide I48 is provided witha T slot I50 to which maybe secured a pair of adjustable dogs II. Theslide is guided by an elongated gib I52. on one side and a pair of shortgibs I53 located on the other side.

Due to the extremely long traversing movement of the wheel head,mechanism has been provided for proportionately shortening this movement so that it is unnecessary to provide a long dog carrying slot, andfurthermore to make it possible to provide a tripping mechanism whichmay be self-contained in the slide. To this end a screw I54 is rotatablysupported adjacent to and parallel to the dog carrying slide I48, andhas threaded thereon a trip member I55 which has a projecting portion onone side adapted to engage the dogs I5I and a guiding portion I56 on theother side which is engaged by a gib I51 to prevent rotation of the nutmember. I One end of the screw is operatively connected to a sprocketwheel I58 which is connected by a chain I59 to a sprocket pinion I60secured to the upper end'of shaft 8|, as more particularly shown inFigure 4. It should now be apparent that as the shaft 8| rotates, itrotates the screw I54, causing the nut member I55 to travel along thescrew. The front of the housing I6I in which this tripping mechanism iscontained is provided with a door I62 on one side and supported onhinges I63 whereby the operator may have ready access to the dogcarrying slide, butstill permitting the entire mechanism to be enclosedand protected. I

The pilot valve plunger I46 may also be shifted manually at will bymeans of the control lever I64 which is keyed to the shaft I65 to which,in

turn, is connected the bell crank I41. Thus, the

pilot valve may be shifted manually at will, or automatically actuatedfrom they moving car- 'rlage. The stop valve plunger I is operated bythe manual control lever I66 which is fixed to shaft I61 journaled inthe upper .part of the casing I6I and provided on the lower end with a.crank arm I68 engaging a cross slot formed in the end of plunger I20.

Means have been provided for obtaining a tarry at each reversal of thewheel carriage and this mechanism is interposed between the directioncontrol valve; I25 and the hydraulic motor 90.

The mechanism comprises a double resistance throttle valve I69 in whichis contained a plunger I10. This plunger has a pair of annular groovesHI and I12 formed therein and adapted to lie opposite ports I13 and I14respectively, which ports are connected by .channels I15 and I16toopposite ends of a shuttle valve I11. The grooves HI and I12 areprovided with tapered portions I18 and I19'which lie opposite ports Iand I8I and serve to form variable hydraulic resistances. The ports I80and I8I are connected to channels I33 and I34 which come from thereversing valve I25. Since the channels I33and I34 are alternatelyconnected to pressure and exhaust it will be apparent that in theposition of the parts shown and with pressure in line I33 that fluidwill flow through port I80 and hydraulic resistance I18, groove I1I,port I13, and channel I15 to the left end of valve I11, while theopposite end is connected to exhaust. This means that the plunger I82should be shifted to the right in the position as shown. When the re- Itwill now be seen that versing valve shifts, however, the pressure inline I34 must pass through the resistance I19 and eventually build up apressure in the right hand end of valve housing I11 and the fluid in theother end must be forced outward through resistance I18. The amount oftime that this will take will depend, of course, upon the value of theresstances I18 and I19. and these may be varied to obtain variouslengths of tarry.

The mechanism for effecting this adjustment consists of a spring I83which acts on one end of plunger I10 to shift it in a direction toreduce the valve of the hydraulic resistances and an adjustable pin I84for limiting the movement. As shown in Figure 10, the pin I84 abuts theend of a crank I85 secured to a rotatable shaft I86. This shaft carriesa forked lever I81 in the end of which is pivotally connected a nut I88threaded on an adjusting screw I89. This adjusting screw has anoperating handle I90 on one end whereby the screw may be rotated tovariably position the stop pin I84. In order to insure that pressurebuilt up in either channel I33 or I34 when the same is connected topressure and to prevent operation of the hydraulic motor 90 until theproper amountof time has elapsed, the plunger I82 is provided with apair of self-contained check valves, indicated generally by thereference numerals I9I and I92. The plunger I82 is provided with annulargrooves I93 and I94 whereby when the plunger I82 is shifted to the rightthe groove I93 will interconnect port I95 with motor line I96 and whenshifted to the left the groove I94 will interconnect port I91 with motorline I98. In other words, the pressure fluid delivered by pump II4 willpass through either groove I93 or groove I94. It will be noted that theports I95 and I91 are connected to the channels I33 and I34 which leadfrom the reversing valve.

In addition, the plunger I 82 is provided with a second pair of groovesI99 and 200 which are always exhaust grooves. In other words, when theplunger I82 is in its right hand position the groove'200 receives theexhaust flow from the motor 90 through channel I98, and when the plungeris in its left hand position the groove I99 receives the exhaust flowfrom motor channel I96. The grooves I99 and 200 have cross bores 20I and202 respectively formed therein which intersect longitudinal bores 203and 204 respectively. The bore 203 is enlarged totreceive a springpressed ball check 205 which is adapted to be opened when the groove I99is in communication with motor channel I96, but which through portI95,'but when port I95 is a pressure port the incoming fluid cannot beforced past the check valve. The same construction is provided in theother end of the valve plunger whereby the exhaust. fluid may be passedfrom channel I98 to part I91 but when port I91 is a pressure port thefluid cannot escape past the check valve. with the parts in the positionshown if the reversing valve be shifted to make port I9 a. pressureport, fluid would'not be able to pass the checkvalve into annular groove200 which means that the pressure would rise and pass through theresistance I19 into the right hand end of valve I11 and continue to riseuntil the valve plunger I82 is shifted into its left hand position, atwhich time the groove I94 would then directly connect port I91 to motorline I98.

If no tarry is desired it will be apparent that as shown in Figure 12,which is attached to the.

the plunger I10 may be adjusted to its extreme left hand positionwhereby the shuttle valve plunger will immediately shift upon reversalin the direction of flow and without delay.

As previously mentioned; the variable delivery pump H2 has a certainrange, and in order to increase this range and maintain the infinitevariation feature, use is made of the constant delivery pump 26, whichhas adisplacement equal to the maximum displacement of the variabledelivery pump, and the output of the constant displacement pump iscombined with the other pump by'means of valve 201. In order to make thesupply from pump 26 available for this purpose, when it is not beingutilized for clamping purposes, an interlock 208, Figure 13, isprovided, and this valve serves to connect channel 52 to channel 2| 1.It will be noted that when the plunger 2l3 of the interlock valve is inits left hand position, as shown, that the line 52 which is underpressure at this time .is connected to port 2I0, whereby the port 2| 2of valve 20! becomes a pressure port and will remain a pressure port atall times when the cross slide is clamped.

The valve 208 is really connected across the lines 52 and 53; and hasone end port connected by branch 203 to channel 52, and the other endport connected by a check valve 2 to line 53, whereby, when channel 52is under pressure the plunger 213 will be shifted'to the left, as viewedin Figure 13; and when channel 53 is under'pressure the plunger 2 [3will be shifted to the right. During normal operation of the machine,the plunger 2 I3 is in the position shown in Figure 13, with pressureexisting in line 52. Whenthe reversing valve 56 is moved to a positionto effect unclamping of the cross slide, it is necessary that theplunger 2l3 be immediately shifted to the right, which the'check valve 2M permits, so that when pressure is reconnected to channel 52 thecircuit will be' in a, condition to cause sufficient pressure to buildup in channel 52 to operate the clamping mechanism. It is, therefore,necessary to prevent dissipation of pressure through the channel 2 I I,which might be connected to the reservoir at any time, and to this end,means have been provided for preventing immediate shifting of plunger2l3 into its left hand position, consisting of the choke coil 2l5 andthe valve associated with plunger H. i In other words, the plunger H hasa cannelure 2|! which, when the plunger H has been retracted by'thespring 69' acting on the lever 69,- serves to interconnect port 2I6, towhich the outlet of the choke coil 2 I 5 is connected, with the exhaustport 2 It. The choke coil and valve act as a delay means to preventshifting of the plunger 2l3 until the slide has been securely clamped.When the plunger 2l3 has completed its shifting movement to the left itinterconnects branchv line 209 to port H and channel 2| I, therebyrendering the output of the constant displacement pump available for usein the supply circuit for motor 90.

It will be noted that when valve plunger 2l9 is I to the right, as shownin Figure 13, the port 2l2 is connected by cannelure 220 to port 22fleading to the exhaust 1ine,222. This permits the constant delivery pump26 to be by-passed to reservoir, but since the fluid must pass throughthe relief valve 223 it will be apparent that .the system will bemaintained full of oil at a low pressure.

The plunger 2l9 is shifted by a crank arm 224 thesame time, a cannelure230 interconnects a branch 23! of return line I28 to the return line222. This is necessarybecause it must be remembered that the variabledisplacement pump is connected in practically a closed circuit to thehydraulic motor 90 and when the fluid from the constant displacementpump is added to one side of this closed circuit, there will be an extraquantity being returned to the pump H4 which cannot be accommodated.Therefore, this connection permits the excess fluid to be by-passed toreservoir through the check valve 223and thereby replenish the supply tothe constant delivery pump.

In Figures 15 and 16, there is shown the means for controlling thedisplacement of the variable delivery pump H2, and this means comprisesa cam 232 attached to the lower end of shaft 233 against which isadapted to bear the pintle 234 of the variable delivery pump. A handle235 is secured to the upper end of shaft 233 whereby the-cam mayberot-ated to vary the displacement of the pump.

As shown in Figure 16, a chart 236 is associated with the handle 235upon which may be placed suitable indicia whereby the operator maydetermine the feed rate for any given setting of the controls. There maybe four concentric arcs, with the indicia on the first are indicatingthe rates available when the constant displacement 1 pump 26 isdisconnected from the circuit, and

with the output .of the variable displacement pump; the indicia on thethird are indicating the rates available when the constant displacementpump has been disconnected fro-m the circuit and the clutch 9| isshifted into its right hand position as shown in Figure 5; and theindicia on the fourth are indicating the rates available when both pumpshave been combined to supply the motor 90, and the clutch 9| is in itsright hand position. It will thus be apparent that there are four rangesof speed and each range is a continuation of the preceding one andwithout steps.

There has thus beenprovi'ded an improved transmission and controlcircuit which is especially adaptable for machines of the roll grindingtype having long traversing movements and in which is incorporated insimplified form mechanism for obtaining all the desirable controlfunctions.

What is claimed is:

1. In a machine tool having relatively movable work and tool supports,the combination of transmission means for effecting saidrelativemovement including an hydraulic motor operatively.

connected to one of said supports, a conduit-system for supplyingactuating medium to the motor including a reversing valve, a variabledelivery having intake and delivery ports connected to said reversingvalve, and means ineluding a shiftable valve interposed in the systembetween said reversing valve and said motor, and responsive to shiftingof said reversing valve, to-decelerate, stop, and accelerate in anopposite direction the moving slide.

2. In a machine tool having relatively movable work and tool supports,the combination of transmission means for effecting said relativemovement including an hydraulic motor operatively connected to one ofsaid supports, a reversing valve, a variable delivery pump havingintakeand delivery ports connected to said reversing valve, means interposedbetween said reversing valve and said motor and responsive to shiftingthereof to decelerate, stop, and accelerate in an opposite direction themoving slide, said means including a delay valve and a valve havingself-contained check valves effective to build up a shifting pressurewhen the flow is reversed to said -motor .to cause a slow movement ofthe lastmentioned valve and thereby a tarry of said motor.

3. In a machine tool having relatively mov able work and tool supports,the combination of transmission means for effecting said-movementincluding an hydraulic motor, a reversing valve,

a variable delivery pump having intake and delivery ports connectedto-said valve, means in said valve for connecting said delivery port forreversible'operation of said motor, a constant delivery pump,selectively operable means for connecting delivery of said constantdisplacement pump for combination with the delivery of said variabledisplacement pump for increasing the movement of said motor to a rapidtraverse rate, a stop valve interposed in the delivery channel of saidvariable delivery pump and eflective to connect the same to the intakeof said variable de'- livery pump, and means for simultaneouslyconnecting the constant delivery pump output to reservoir.

, 4. In. a grinding machine having relatively movable tool and worksupports and an hydraulic motor for effecting said movement, thecombination of a tarry mechanism including a shiftable plunger having apair of self-contained check valves, a pair of ports connected tosaidmotor, a'second pair of ports alternatively connectible to intake anddelivery ports of a variable delive y pump, said check valves beingeffective to pass return fluid from said motor and block delivery offluid to said motor, and means responsive to the pressure of saidblocked fluid to shift said plunger into a position by-passing saidcheck valve when subject to pressure.

5. In a machine tool having a work support and a tool support, thecombination with hydraulic means for effecting relative translationbetween the-supports including an hydraulic motor and a reversing valvetherefor, of a tarry valve interposed between the reversing valve andthe motor, said tarry valve including a shiftable plunger, a pair ofports connected to said reversing valve and adapted to be alternatelysubjected to pressure thereby, branch connections from each of saidports to the respective ends of said valve, saidconnectionshavingvariable resistancestherein, means in the valve responsive toreversal of flow therethrough to block the pressure flow to said motor,and simultaneously cause a slow increase in pressure on one end of saidvalve to effect shifting of the same, and means effective uponcompletion of said shifting movement to connect the pressure flow tosaid motor.

6. In a grinding machine having a work support and a grinding wheelsupport the combination of transmission mechanism for traversing one ofsaid supports relative to the other at infinitely variable ratesincluding a rotary hydraulic motor, a variable displacement pump, aconstant first-named pump to produce a second range of speeds, and meansto adjust said rate changer to produce a plurality of other ranges ofspeeds;

"7. In a grinding machinehaving a work support and a grindingwheel'support, the combination of a transmission .for effecting relativemovement between the supports including a final drive shaft operativelyconnected to the moving support, a rotary hydraulic motor, differentratio gear trains continuously driven by said motor, a

plurality of pumps selectively connectible in different combinations tosaid motor to yield a plurality of rates of actuation thereof, a manualactuator for said final shaft, means to couple selectively said manualactuator to said shaft, means to couple selectively either of said geartrainsto said shaft, said last-named means also. being. operable todisconnect simultaneously both of said gear trains from said shaft, anda common control for all of said coupling means.

8. In a grinding machine having a work support and a grinding wheelsupport, the combination of a transmission for effecting relativemovement between the supports including a final drive shaft operativelyconnected to the moving support, a rotary hydraulic motor, differentratio gear trains continuously driven by said motor, a plurality ofpumps selectively connectible in different combinations to said motor toyield a plurality of rates of actuation thereof, a manual actuator forsaid final shaft, means to couple selectively said manual actuator tosaid shaft, means to couple selectively either of said gear trains tosaid shaft, said last-named means also being operable to disconnectsimultaneously both of said gear trains from said shaft, a commoncontrol lever for all of said coupling means, and an interlocking guideplate for said lever whereby when said manual actuator is connected tothe final shaft, said motor will be disconnected therefrom and viceversa.

9. In a grinding machine having relatively movable tool and worksupports and a fluid operable motor for effecting said movement inopposite directions, the combination with a pump for supplying fluid tosaid motor and a reversing valve, of a tarry mechanism including ashiftable plunger having a pair of self-contained check valves, a pairof motor channels, a second pair of channels adapted to be reversiblyconnected by said valve to the output of said pump, meansinterconnecting said plunger with all of said channels whereby saidcheck valves are effective to pass return fluid from said motor andblock delivery of fluid to said motor upon shifting of said reversingvalve, .andmeans movable in response to the pressure of said blockedfluid to shift said plunger into a position rendering said check valvesineifective.

' 10. In a machine tool having a work support and a grinding wheelsupport, the combination of an hydraulic circuit for effecting relativemovement between the supports including a fluid oper- 76 able motoroperatively connected to the moving support, a variable delivery pumphaving intake and delivery channels connected thereto, a stop valve forinterconnecting said channels to stop said motor, a reversing valvehaving pressure and return ports adapted to be separately connected tosaid pump channels by said'stop valve, variable automatic tarrymechanism interposed in the circuit connecting said reversing valve tosaid motor, and a pilot valve and control circuit for controlling theshifting of said reversing valve.

11. A machine tool having relatively movable work and tool supports, thecombination of transmission means for effecting said movement includinga' hydraulic motor, an actuating pump therefor and means for controllingthe actuation of the motor by the pump including a pilot valve, areversing valve operable by the pilot valve, an auxiliary reversingvalve coupled with the first mentioned reversing valve and actuablethereby for determining the ultimate coupling of the actuating fluidfrom the pump to the motor, and an adjustable tarry mechanism coupledwith said second reversing valve for controlling the rate of movementthereof.

12. A machine tool having relatively movable work and tool supports, thecombination of transmission means for effecting said movement includinga hydraulic motor an actuating pump therefor and means for controllingthe actuation of the motor by the pump including a pilot valve, areversing valve operable by the pilot valve, an auxiliary reversingvalve coupled with the firstmentioned reversing valve and actuablethereby for determining the ultimate coupling of the actuating fluidfrom the pump to the motor, an adjustable tarry mechanism coupled withsaid second reversing valve for controlling the rate of movementthereof, and additional means for diverting the flow from said pump asrespects said motor and valve mechanisms.

13. In a machine tool embodying a support and a plurality of membersmovable thereon with respect thereto, transmission means for efiectingmovement of the supports including-hydraulic motors individual to therespective supports, a closed circuit including a first fluid pumpindividual to one of said motors for controlled actuation thereof, asecond hydraulic pum, and means for selectively coupling said pumpwith'either of said motors, said means including discharge con- ;dultsindividual to the respective pumps, and valve means for coupling therespective conduits and simultaneously establishing a reservoir connection for said first motor whereby the two pumps may be additivelyemployedior actuation of one of said motors.

1 4. In a machine tool embodying a support and a plurality of membersmovable thereon with respect thereto, transmission'means for efiectingmovement of the-supports including-hydraulic motors, individual to therespective supports, a closed circuit including a first fluid pumpindividual to one of said motors for controlled actuation thereof, asecond hydraulic pump, and means ior selectively coupling saidpump witheither of said motors, said means including discharge conduitsindividual to jthe respective pumps, and valve means for coupling therespective conduits and simultaneously establishing a reservoirconnection for said first motor whereby the two pumps may beadditivelycmployed for actuation of one ofsaid motors, and"selec'ormeans for rendering either or both of said pumps ineffecthe i'oractuation of said motors.

15. In a machine tool having relatively movable work and tool supports,means for clamping one of said supports and hydraulic actuators foreffecting movements and clamping of the supports, means for effectingcontrolled hydraulic actuation'of said parts including a hydraulic pumpselectively coupled with said support motors and operatively associatedwith the clamp mechanism, a plurailty of reversers individual to themotor and clamp mechanisms, a first interlock mechanism between theclamp control reverser and one of the motor reversers for determiningthe sequential operation of said parts, conduit means extending from thepump output to the second motor reverser, and a hydraulic interlockoperatively associated with one of the first-named reversers fordetermining the flow through the conduit to said last-named reverser.

16. In a machine tool having relatively movable work and tool supports,means for clamping one of said supports and hydraulic actuators foreffecting movement and clamping of the supports,

means for effecting controlled hydraulic actua- 1 second motor reverser,a hydraulic interlock operatively associated with one of the first-namedreversers for determining the flow through the conduit to saidlast-named reverser, a first tarry mechanism for determining the flowcondition in said interlock controlled conduit, and a second tarrymechanism for determining the time lag in directional reaction of thefluid transmitted by the conduit on the second support shifting motor inresponse to given adjustments of its reverser.

17.- A machine tool having relatively movable work and tool supportsincluding means for shifting one of said supports and means for clampingsaid support against shifting movement, a first hydraulic motor foreffecting shifting of the support, an additional hydraulic motormechanism for controlling the clamp, and a hydraulic control andactuation system for said parts including a source of hydraulic fluid, afirst reverser for coupling the hydraulic medium to actuate the supportin reverse directions, a second reverser coupling the hydraulic fluidfor movement of the clamp into engaging or releasing position, a singleactuator controlling the movement of both reversers, an interlockbetween said reversers whereby coupling of hydraulic medium foractuation of the support is prevented when the clamp is engaged, and adelay mechanism for determining the sequential operation of thereversers by their common actuator.

18. A machine tool having relatively movable work and tool supportsincluding means for shifting one of said supports and means for clampingsaid support against shifting movement, a first hydraulic motor foreffecting shifting of the support, an additional hydraulic motormechanism for controlling the clamp, and a hydraulic control andactuation system for said parts including a source of hydraulic fluid, afirst reverser for coupling the hydraulic medium to actuate the supportin reverse directions, a second reverser coupling the hydraulic fluidfor move-.

ment of the clamp into engaging or releasing position, a single actuatorcontrolling the movement of both reversers, an interlock betweensaidreversers whereby coupling of hydraulic medium for actuation of thesupport is prevented when the clamp is engaged, a delay mechanism fordetermining .the sequential operation of the reversers by their commonactuator, a second shiftable support, a hydraulic motor for actuationthereof, and means for conditioning the hydraulic circuit by way of oneof said reversers whereby the hydraulic actuating medium is renderedavailable for actuation of said second support shifting motor. a

19. A machine tool having relatively movable work and tool supportsincluding means for shifting one of said supports and means for clampingsaid support against shifting movement, a first hydraulic motor foreffecting shifting of the support, an additional hydraulic motormechanism for controlling the clamp, and a hydraulic control andactuation system for said parts including a source of hydraulic fluid, afirst reverser for coupling the hydraulic medium to actuate the supportin reverse directions, a second reverser coupling the hydraulic fluidfor movement of the clamp into engaging or releasing. position, a singleactuator controlling the movement of both reversers, an interlockbetween said reversers whereby coupling of hydraulic medium foractuation of the support is prevented when the clamp is engaged, a delaymechanism for determining the sequential operation of the reversers bytheir common actuator, a second shiftable support, a hydraulic motor foractuation thereof, means for conditioning the hydraulic circuit by wayof one of said reversers whereby the hydraulic actuating medium isrendered available for actuation of said second support shifting motor,and an additional serially arranged reversing mechanism in said circuitfor determining the direction of actuation of said second support motor.

20. A machine tool having relatively movable work and tool supportsincluding means for shifting one of said supports and means for clampingsaid supportagainst shitting movement, a first hydraulic motor forefiecting shifting of the support, an additional hydraulic motormechanism for controlling the clamp,- and a hydraulic control andactuation system for said parts including a source of hydraulic fluid, afirst reverser for coupling the hydraulic medium to actuate the supportin reverse directions, asecond reverser coupling the hydraulic fluid formovement of the clamp into engaging or. releasing position, a singleactuator controlling the movement of both reversers, an interlockbetween said reversers whereby coupling of hydraulic medium foractuation of the support is prevented when the clamp is engaged, a delaymechanism for determining the sequential operation of the reversersbytheir common actuator, a second shiftable support, a hydraulic motorfor actuation thereof,' means for conditioning the hydraulic circuit byway of one of said reversers whereby the hydraulic actuating, medium isrendered available ior actuation of said second support shitting motor,an additional serially arranged reversing mechanism in said circuit fordetermining the direction of actuation of said second support motor, andadditional means for i'endering said available hydraulic mediumineflective as respects said second support shifting motor.

21. A machine tool having relatively movable work and tool supportsincluding means for shirtin: one of said supports and means for clampingsaid support against shifting movement, a first hydraulic motor foreffecting shifting of thesupport, an additional hydraulic motormechanism for controlling the clamp, and a hydraulic control andactuation system for said parts including a' source of hydraulic fluid,a first reverser for coupling the hydraulic medium to actuate thesupport in reverse directions, a second reverser coupling the hydraulicfluid for movement of the clamp into engaging or releasing position, asingle actuator controlling the movement of both reversers, an interlockbetween said reversers whereby coupling of hydraulic medium foractuation of the support is prevented when the clamp is engaged, a delaymechanism for determining the sequential operation of the reversers bytheir common actuator, a second shiftable support, a hydraulic motor foractuation thereof, means for conditioning the hydraulic circuit by wayof one of said reversers whereby the hydraulic actuating medium isrendered available for actuation ,of said second support shifting motor,an additional serially arranged reversing mechanism in said circuitior'detennining the direction of actuation of said second support motor,said mechanism including a primary and a secondary reversing valve, andadditional delayed action combined decelerating and reversing valveactuable by the secondary reverser, and delay means for determining theresponsiveness of the lastmentioned valve to the reverser in couplingthe controlled hydraulic actuating medium to said second supportshifting motor.

22. A machine tool having relatively movable work and tool supportsincluding means for shifting onev of said supports and means forclamping said support against shifting movement, a first hydraulic motorfor efiecting shifting of the support, an additional hydraulic motormechanism for controlling the clamp, and a hydraulic control andactuation system for said parts including a source of hydraulic fluid, afirst reverser for coupling the hydraulic medium to actuate the supportin reverse directions, a second reverser coupling the hydraulic fluidfor movement of the clamp into engaging or-releasing position, a singleactuator controlling the movement of both reversers, an interlockbetween said reversers whereby coupling of hydraiilic medium foractuation of the support is prevented when the clamp is engaged, a delaymechanism for determining the sequential operation of the reversers bytheir common actuator, a second shiftable support,-a hydraulic motor foractuation thereof, means for conditioning the hydraulic circuit by wayof one of said reversers whereby the hydraulic actuating medium isrendered available for actuation of said second support shifting motor,an additional serially arranged reversing mechanism in said circuit fordetermining the direction of actuation of said second support motor,said mechanism including a primary and a secondary reversing valve, andadditional delayed action combined decelerating and reversing valveactuable by the secondary reverser, delay means for determining theresponsiveness of the last-mentloned valve to the reverser in couplingthe controlled hydraulic actuating medium to said second supportshifting motor, and means in serial relation with said last-mentionedreversing mecha-.

nism for determining the effectiveness of the hydraulic medium asrespects said second sup-v port motor.

HANS ERNST.

ALBERT H, BALL. 1

